Systematic review of nerves at risk at the wrist in common surgical approaches to the forearm: Anatomical variations and surgical implications.

Three commonly used approaches to the forearm in orthopedic surgery are Henry's, Thompson's, and the ulnar approach, each of which has the potential to cause injury to nerves around the wrist. Preserving these nerves is important to prevent complications such as neuroma formation and motor and sensory changes to the hand. We conducted a review of the literature to assess the nerves at risk and whether 'safe zones' exist to avoid these nerves. An independent reviewer conducted searches in Embase and MEDLINE of the literature from 2010 to 2020. A total of 68 papers were identified, with 18 articles being included in the review. Multiple nerves were identified as being at risk for each of the approaches described. In the anterior approach, the palmar cutaneous branch of the median nerve (PCBMN) is most at risk of injury. An incision immediately radial to the flexor carpi radialis (FCR) or directly over the FCR is most likely to avoid injury to both superficial branch of the radial nerve (SBRN) and PCBMN. With Thompson's approach, the safest zone for an incision is directly over or slightly radial to Lister's tubercle to avoid injury to SBRN and lateral cutaneous nerve of the forearm. For the ulnar approach, a safe zone was shown to be on the ulnar side of the wrist around the ulnar styloid (US) when the forearm was in supination or a neutral position to avoid injury to the dorsal branch of the ulna nerve (DBUN). Care must be taken around the US due to the density of nerves and the proximity of the last motor branch of the posterior interosseous nerve to the ulnar head. This review highlighted the proximity of nerves to the three most common surgical incisions used to access the forearm. In addition, anatomical variations may exist, and each of the nerves identified as being at risk has multiple branches. Both factors increase the potential of intraoperative damage if the anatomy is not properly understood. The surgeon must adhere carefully to the established approaches to the wrist and distal forearm to minimize damage to nerves and optimize surgical outcomes for the patient.

A Case Report of Unicompartmental Knee Arthroplasty Fracture of the Femoral Component.

Introduction: Unicompartmental knee arthroplasty (UKA) is performed with yearly rate of 9% in UK, and <8% in USA. It has been shown to be a successful and less invasive alternative to complete knee arthroplasty in certain patients total knee arthroplasty (TKA). Fracture of the femoral component after (UKA) has never been reported in the literature. Consequently, to investigate the major causes and mechanisms of (UKA) failure, we present a case of femoral component failure following (UKA). Case Report: A 62-year-old patient with 2 years following an UKA presented with a right pain, stiffness, and gait abnormalities. After taking full history and careful examination and obtaining a new radiograph, a fracture of the femoral component was revealed. A revision surgery with TKA has been done, and the outcome was assessed regularly, and good results were achieved. Conclusion: The exact reason for a femoral component fracture following UKA is yet unknown. To make an early diagnosis and avoid the need for complex knee revision surgeries, long-term follow-up is crucial for early detection of the clinical signs and symptoms of implant failure.